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Questions tagged [qgis-2]

Version 2.x of QGIS (previously Quantum GIS)

6
votes
0answers
82 views

Show Symbol (e.g. City-Marker) only when an associated label can be displayed

I'm building a map for a certain region with many cities to be displayed. Some of the smaller cities should only be displayed if they don't overlay bigger cities. While the labels of the smaller ...
5
votes
0answers
411 views

QGIS Align Rasters how to retain pixel values?

I am attempting to align and then merge a number of rasters of the same resolution and extent, but where the pixels are slightly misaligned (creating small gaps when merged). This works fine using the ...
5
votes
0answers
370 views

Postgis sequence in QGIS not working

I have a Multipolygon-Layer stored in a Postgis-database. The primary key field 'gid' is SERIAL. When trying to add a new polygon in QGis (LYON 2.12.1 on OSX El Capitan), the attributes form shows me: ...
5
votes
0answers
737 views

How can I programmatically remove a layer from the QGIS composer legend without removing it from the map canvas?

I am working on a QGIS Python plugin which includes automated map production. I use a series of map templates, each of which has a main map, an overview map (with a layer set different to the main ...
4
votes
0answers
197 views

QGIS (Python) crashing when trying to iterate through layers in a thread

Version: 2.18, and I cannot upgrade to 3. I am adapting a script I found elsewhere on stackexchange which is supposed to indefinitely refresh all layers in the TOC at one-second intervals. This is ...
4
votes
0answers
186 views

Get signal on delete group on QGIS 2.18.16

I tried : QgsProject.instance().layerTreeRoot().willRemoveChildren.connect(self.onWillRemoveChildren) It works if I delete a group within in the root node. But if I delete a layer within a group ...
4
votes
0answers
150 views

QGIS 2.18.14 vector Clip analysis producing erroneous result

I am trying to perform a vector clip analysis (vector-->geoprocessing tools pull-down menu) using two complicated vector layers and am getting erroneous results. The clip 'Input layer' is shown here: ...
4
votes
0answers
334 views

How to create text buffer in the legend- QGIS 2.18?

I work with this polygon layer and this is my map composer: I used the labels with Text Buffer (yellow and red), and I try to find how I can make the same text buffer in the layer name in the legend. ...
4
votes
0answers
408 views

Computing the slope of a road using DEM

I work with QGIS 2.14 and I want to create a map of road network showing the slope of each road with at least this scale: <3%; 3-5%; 5-7%; 7-9%; >9%. I already have a vector layer of roads and the ...
4
votes
0answers
3k views

Is there an “undo” button in QGIS 2.18?

In ArcGIS there an option of "undo" button I seek this option in order to return my steps if it necessary. I try to find such option in the menu and didn't found any like it. What can I do?
4
votes
0answers
61 views

Is there a way to customize the Options dialog in QGIS 2.14.6?

I'm creating a deployment package to update QGIS from V2.8 (wien) to V2.14 (essen (LTR)). In QGIS 2.14 there is a new "Advanced" section under "Settings > Options", see screenshot: Can this menu ...
4
votes
0answers
620 views

Qgis 2.8.9-Wien Attribute table Update Fields Error

I can't update fields in the Attribute table. I get an error when I select Update All and Update Selected: An error occurred while evaluating the calculation string: No root node! Parsing failed? ...
4
votes
0answers
702 views

Zonal Statistics tool not working with QGIS?

I wanted to try the QGIS 2.14 zonal statistic tool but it doesn't work.The system says: not a sequence See log for more details The SAGA Zonal Statistic tool works fine. It also doesn't work with ...
4
votes
0answers
156 views

Raster calculators in SAGA return incorrect results

Here's a sample of my dataset (one cell) with 28 different raster values, representing 28 individual Float32 rasters with identical parameters. 0.0000264434, 0.0049953502, 0.0007529828, 0....
4
votes
0answers
339 views

Rule-based labeling and the Data defined placement options are not working together (QGIS 2.12, 2.14)

After setting "Rule-based labeling" to my layer (new feature since QGIS 2.12), my data defined labeling is not working any more (see labeling tools on the right side): Going back to "Show labels for ...
4
votes
0answers
252 views

SAGA Tool in QGIS Error: Load table: Proj.4-WKT Dictionary… failed

I have some problems with running SAGA tools in QGIS. I've downloaded and installed the software via the OSGeo4W Installer. It downloaded QGIS 2.12 and Saga 2.1.2. I wanted to use the Tool "Shapes To ...
4
votes
0answers
498 views

Different scale of basemap after exporting to PDF/Image

After creating and exporting my map to pdf/tif obviously there are different scales of the basemap in the exported file compared to the map I created in the printcomposer. See pictures... I am using ...
4
votes
0answers
1k views

How can I label the pie charts in QGIS so the labels are written under the diagrams?

How can I label the pie charts in QGIS so the labels are written under the diagrams? My pie-charts are representing localities: such as villages, towns, cities. So, I want that their names appear ...
4
votes
0answers
1k views

WMTS from MapProxy in QGIS and/or ArcGIS

My company wants to use imagery from a another company internally for a contract. That company's WMS has a 5+ second latency. Which I'm told is unacceptably slow. So I set up MapProxy and seeded the ...
3
votes
0answers
21 views

QGIS tile cache not working

I'm new to QGIS and work on an air-gapped system where I have access only to QGIS 2.14.9-Essen. I create a WMS layer, which "works" but performance is abysmal. So I enable caching (Settings > Network) ...
3
votes
0answers
54 views

Unable to compute intersection between two polygons using PyQGIS?

I have two polygons in different layers. I am trying to find the intersect between the two polygons. Below a figure showing my test case. I initially wanted to find the intersect between the green ...
3
votes
0answers
59 views

Standalone Application QgsCoordinateReferenceSystem fails without OSGeo environment

I am writing a simple standalone QGis application. My code is like this: class MainForm(QtGui.QMainWindow, Ui_MainWindow): def __init__(self): super(MainForm, self).__init__() ...
3
votes
0answers
90 views

QGIS: Cropland Data Layer - how to add class names to .tif file?

I'm working with a clip of the Cropland Data Layer (raster), which has a number for each value coded to a crop type. I want to add these crop type / class names to the .tif file (and have them show up ...
3
votes
0answers
288 views

Merging asc files in QGIS?

I am trying to merge 8 .asc files using merge option in QGIS 2.4 but when I do that it makes like contour of the file when I want to merge the files together. .ASC Files: Result after merging:
3
votes
0answers
82 views

How to transfer QGIS configurations to latest version?

I have QGIS 2.18.11 on my machine. There are saved wms, wfs and DB connections. After installing QGIS 3.0 I can see saved wms connections but no DB connection is listed in 3.0. Collegue's problem is ...
3
votes
0answers
739 views

Installing plugins for QGIS 2.18 on mac

I can't install any plugins on QGIS since updating to 2.18 (I am running High Sierra). I am connected to the QGIS Plugin Repository yet receive the error message: Plugin installation failed:Failed ...
3
votes
0answers
204 views

Why does Contours plugin crash QGIS 2.18?

I am running QGIS 2.18 on a mac and trying to use the Contours plugin. I've never had problems with it before but then I updated QGIS using Kyngchaos. Now Contours crashes QGIS when I choice "Filled ...
3
votes
0answers
114 views

QGIS Custom Qt Widgets on OSX

When I install QGIS on windows I get a bunch of custom widgets in Qt Designer On OSX I can't figure out how to get those same widgets to appear in Qt Designer. I have set my environment variables ...
3
votes
0answers
2k views

K-Means clustering in QGIS (Attribute based clustering)

In the 2.18.4 and 2.18.5 version of QGIS K-means clustering was moved to a plugin called 'Attribute based clustering'. However, I am working with a virtual raster dataset (vrt.) and the current ...
3
votes
0answers
159 views

Linking “value maps” together in PostGIS/QGIS where the values are user editable?

This is related to Limiting available values in dropdown field of QGIS form according to value selected in previous field?. Even though this has been marked as resolved the answer is not what I am ...
3
votes
0answers
329 views

minidump written to C: in QGIS PLUGIN

I have created a simple QGIS script using QGIS 2.18.3 and windows 10 and it works fine without errors.But I want to move that script to another PC where I have QGIS 2.6 and windows 7. I first copy-...
3
votes
0answers
88 views

Select features tool- QGIS 2.14

When i select polygon with select tool- the whole polygon colored: i seek a way to select the shape only with outline, as it possible in ArcGIS. I know i can change the opasitiy in "Map Tool" but ...
3
votes
0answers
150 views

Adding field to shp subset layer using PyQGIS?

This is an independent followup from my previous question: QGIS Python generate index field I have two files (points.shp, polylines.shp), each with a variable amount of sublayers of the given ...
3
votes
0answers
1k views

How do I export a 16-bit image from QGIS?

Could someone explain how to export from QGIS a 16bit image. I have imported data and coloured it as I want, but need to export it as a 16bit image, as 8bit is giving a terracing effect.I believe I ...
3
votes
0answers
677 views

Plugins incorrectly being disabled due to “causing QGIS crash”

I have QGIS 2.14.0 installed on my machine (W7 x64, AMD FX-8150 3.6GHz, 8GB RAM, SSD) and I'm having issues with plugins not opening by default when I open QGIS. The message I get (for each plugin ...
3
votes
0answers
967 views

QGIS 2.14 fails to install on Ubuntu 14.04

My previously working installation of QGIS 2.14 on Ubuntu 14.04 suddenly failed to start QGIS. I have been trying to reinstall QGIS without success. I have tried several ways to completely uninstall ...
3
votes
0answers
329 views

QGIS 2.14 Processing plugin crashes - TypeError: must be string, not None

I've recently installed 2.14, and it worked fine for the first couple of days (Appart from Grass tools), including several program and computer reboots. Today I had this error show up Couldn't load ...
3
votes
0answers
930 views

How to rotate symbols in QGIS

I have a vector symbol that I am using rule based style with. In the Rule properties tab I click on the SVG marker and change the "rotation" which is a field I have made to handle to the rotation ...
3
votes
0answers
166 views

How can I see the 'Custom Options' metadata following Save As in QGIS?

In QGIS 2.10 Pisa, I've right-clicked a layer in the TOC and used Saved As ... to save a shapefile with a new name. During this process, I used the Custom Options (Data Source and Layer) to include ...
3
votes
0answers
330 views

How to refresh or update a vrt layer in Qgis?

When using the QGIS SpreadSheet Layers plugin, how do I update the SQLite query without closing and reopening QGIS? I cannot see a "watch file" equivalent. The plugin creates and uses a *.vrt file ...
3
votes
0answers
647 views

SAGA Raster Calculator, ifelse doesn't return specified value exactly

I am using the SAGA Raster Calculator in QGIS 2.6 to change NaN values to zero and that part is working great, however the specified 'if' value is being altered slightly. I have developed a work ...
3
votes
0answers
205 views

PyQGIS: standard and advanced linear referencing possibilities

I'm aware of the existence of the following QGIS plugins: QChainage Event layer linear referencing LRS Although, all of these tools offer some linear referencing capabilities, I find that they lack ...
3
votes
0answers
272 views

QGIS Topology checker wrong results?

I am trying to understand topology checker results and frankly i dont get it - probably i am doing something wrong. Source - Point layer Target - Polygon layer Must be inside - that is working as ...
3
votes
0answers
213 views

Editing Cursor for GPS live tracking in QGIS 2.4

I am interested in using QGIS 2.4 for vessel navigation due to its ability to display NOAA vector charts or BSB's as well as user created shapefiles. I currently oversee a project that requires ...
3
votes
0answers
275 views

How to move feature using python console in qgis

i am building a qgis plugin that can create as much copies of a selected feature as i want and paste it to my required place.I have code to copy and paste feature select = iface.activeLayer()....
3
votes
0answers
853 views

QGIS 2.4.0 Mac Yosemite compatibility

I just upgraded to the Beta 2 version of MacOS 10.10 ("Yosemite"). I'm getting an error when I try to "drag and drop" shape files into QGIS. I'm running QGIS 2.4.0, GDAL 1.11, and MATPLOTLIB 1.3.1. ...
3
votes
0answers
891 views

How to export data from sql server into shapefile in the decimal format in QGIS 2.4?

The last couple of days, I have been working on exporting data from SQL to a shapefile in QGIS 2.4. While converting into a shapefile, the data type changes automatically from Float to Integer in the ...
3
votes
0answers
283 views

How can I change the NoData value in QGIS 2.x using the python console

I'm trying to add a NoData value to a single band raster image in QGIS 2.0 using the python console but can't find the right bit of code to do it. Here's what I see on the console: >>> ...
2
votes
0answers
72 views

Inverting shapefile in QGIS 2.18?

I asked a question earlier about how to invert my file "hydropolys.shp" from a vector of ocean and seas to a vector of land and got sent to here, but I am experiencing issues where using the "...
2
votes
0answers
58 views

Closest features from a mouse click – altering selection if a feature has already been found

I have a working code that selects 4 closest points from a mouse click and creates a convex hull using the selection. def canvasReleaseEvent(self, mouseEvent): """ Each time the mouse is ...